Human beings have been thinking logically (and sometimes illogically) since the earliest era of human existence. However,
they have not always been aware of the general principles that distinguish logical from illogical forms of thought. Logic,
as an academic subject, is the systematic study of those principles. The logician asks, Which rules should we follow
if we want our reasoning to be the best possible?

The rules of logic are guides to correct reasoning just as the rules of arithmetic are guides to correctly adding, subtracting,
multiplying, and dividing numbers, the principles of photography are guides to taking good photos, and so on. You can
improve your reasoning by studying the principles of logic, just as you can improve your number-crunching abilities by
studying the principles of mathematics. Because correct reasoning can be applied to any subject matter whatsoever, the
number of potential applications of logical theory is practically unlimited.

The Greek philosopher Aristotle (384–322 BC) wrote the first book on the standards of correct reasoning and later wrote four
additional treatises on the subject. Thus, in five highly original (and extremely complex) works, collectively known
as the
Organon (Greek for “tool,” as in “general tool of thought”), Aristotle launched the study of the principles of correct
reasoning and earned the title historians have conferred on him: founder of logic.
[i] The noted twentieth-century logician and philosopher Benson Mates writes:

[W]e can say flatly that the history of logic begins with the Greek philosopher Aristotle . . . Although it is almost a platitude
among historians that great intellectual advances are never the work of only one person (in founding the science of geometry
Euclid made use of the results of Eudoxus and others; in the case of mechanics Newton stood upon the shoulders of Descartes,
Galileo, and Kepler; and so on), Aristotle, according to all available evidence, created the science of logic absolutely
ex nihilo.
[ii]

Logic was first taught as an academic subject in the universities of ancient Athens, Greece during the fourth century BC,
making it one of the oldest of all academic subjects. For twenty-five hundred years, it has been considered a core academic
requirement at institutions of higher learning around the world. Logic remains part of the core curriculum around the
world today because the principles of correct reasoning can help anyone reason more accurately, no matter what subject,
making it an all-purpose “tool kit” for your mind.

Major Divisions of Logic

Formallogic studies the abstract patterns or forms of correct reasoning. Here the focus is on
form rather than
content, that is, on the logical structure of reasoning apart from what it is specifically about. Since ancient times,
logicians have used special symbols and formulas, similar to those used in mathematics, to record the abstract logical
forms they have discovered. This is why formal logic is sometimes also called “symbolic logic” or “mathematical logic.”

Informallogic studies the non-formal aspects of reasoning—qualities that cannot be accurately translated into abstract symbols.
This is why informal logic for the most part dispenses with special symbols and formulas. In this division of logic,
the focus is often reasoning expressed within everyday language.

Elements

Logical theory begins with the notion of an
argument, which is defined as one or more statements, called “premises,” offered as evidence, or reason to believe,
that a further statement, called the “conclusion,” is true. In plain terms, an argument is reasoning offered in support
of a conclusion. Arguments are part of everyday life. You present one every time you put your reasoning into words to
share it with others. In the following example, the premises are marked P1 and P2, and the conclusion is labeled C.

P1: All songwriters are poets.

P2: Bob Dylan is a songwriter.

C: Therefore, Bob Dylan is a poet.

The second building block of logical theory is the distinction, first noted by Aristotle, between deductive and inductive
reasoning. A
deductive argument aims to establish its conclusion with complete certainty, in such a way that if its premises all
are true, then its conclusion
must be true. Put another way, the underlying claim in the case of a deductive argument is that it is not even possible
the premises all are true and the conclusion is false. For example:

P1. Tiny Tim played the ukulele.

P2. Anyone who plays the ukulele is a musician.

C. Consequently, Tiny Tim was a musician.

Deductive arguments aim for certainty and nothing less. If a deductive argument succeeds in its aim, it is a
valid deductive argument. If it does not, it is an
invalid deductive argument. A deductive argument is said to be
sound if it is (a) valid and (b) all of its premises are true. The following deductive argument is clearly valid
although it is not sound.

P1. All students are millionaires.

P2. All millionaires drink vodka.

C. Therefore, necessarily, all students drink vodka.

In contrast, the following argument is invalid (and hence also unsound).

P1. Ann and Sue are cousins.

P2. Sue and Rita are cousins.

C. So, Ann and Rita
must be cousins.

The following argument hits the target—it is both valid and sound.

P1. All whales are mammals.

P2. All mammals are warm-blooded.

C. Ergo, all whales are warm-blooded.

Deductivelogic is the study of the standards of correct deductive reasoning. Here is an example of a law of deductive logic.
Let A, B, and C be variables ranging over terms that stand for categories—words such as cats, dogs, people, trucks, and
so forth. Aristotle proved that the following form or pattern of reasoning, named
Barbara by logicians in Europe during the Middle Ages, is a valid form, meaning that any argument—about any subject—that
exactly follows this pattern is valid.

The Barbara Argument Form

All B are C.

All A are B.

Therefore, necessarily, all A are C.

Let’s test Barbara. If we replace the variable A with
sparrows, the variable B with
birds, and substitute
animals for the variable C, we get the following “substitution instance” of the corresponding form:

P1. All birds are animals.

P2. All sparrows are birds.

C. Therefore, necessarily, all sparrows are animals.

This argument is clearly valid. Aristotle proved that any argument that exactly follows this form of reasoning is valid.
For instance:

P1. All mammals are animals.

P2. All cats are mammals.

C. Therefore, necessarily, all cats are animals.

To return to Barbara for a moment, notice that the form is not about any particular subject—it is an abstract pattern with
no material content. Barbara is all form and no content. Aristotle discovered that an argument’s validity is always a
function of its form rather than its content. You can learn a lot about reasoning by studying valid argument forms. Logicians
have catalogued hundreds of them. The study of logical forms is valuable, for if your argument follows a valid form,
then it is guaranteed to be valid and therefore your conclusion must be true if your premises are true. As you may have
guessed, formal logic and deductive logic overlap in the study of valid patterns of reasoning, of which there are many.

An
inductive argument, on the other hand, does not aim to show that its conclusion is certain. Rather it aims to show
that its conclusion is probably, though not definitely, true so that if its premises are true, it is likely that its
conclusion is true. This argument aims to establish its conclusion with a probability less than one:

P1. Joe has eaten a Dick’s Deluxe burger for lunch every day for the past month.

C. So, it is very probable that he will have a Dick’s Deluxe for lunch tomorrow.

If an inductive argument achieves its aim, it is a
strong argument.
An inductive argument that does not achieve its aim is a
weakargument. An inductive argument is said to be
cogent if it is (a) strong, and (b) all of its premises are true. The following inductive argument is strong although
it is surely not cogent:

P1. We interviewed one thousand people from all walks of life and every social group all over Seattle over a ten-week
period, and 90 percent said they do not drink coffee.

C. Therefore, probably about 90 percent of Seattleites do not drink coffee.

The following argument is clearly weak:

P1. We interviewed one thousand people from all walks of life as they exited coffee shops in Seattle, and 98 percent
said they drink coffee.

C. Therefore, probably about 98 percent of Seattleites drink coffee.

The following argument is better—it is strong as well as cogent:

P1. NASA announced that it found evidence of water on Mars.

P2. NASA is a scientifically reliable agency.

C. Therefore it is likely there is or was water on Mars.

Inductive logic is the study of the standards of good inductive reasoning. One inductive standard pertains to
analogical arguments—arguments that take the following form:

A and B have many features in common.

A has attribute
x and B is not known
not to have attribute
x.

Therefore, B probably has attribute
x as well.

For instance:

P1. Monkey hearts are very similar to human hearts.

P2. Drug X cures heart disease in monkeys.

P3. Drug x is not known to not cure heart disease in humans.

C.Therefore, drug X will probably cure heart disease in humans.

Analogical arguments can be evaluated rationally. Here are three principles commonly used to judge their strength:

The more attributes A and B have in common, the stronger the argument, provided the common features are relevant to the
conclusion.

The more differences there are between A and B, the weaker the argument, provided the differences are relevant to the
conclusion.

The more specific or narrowly drawn the conclusion, the weaker the argument. The more general or widely drawn the conclusion,
the stronger the argument.

Informal and inductive logic overlap in the study of the many non-formal aspects of inductive reasoning, which include guides
to help us improve our assessments of probability.

Information Spillover

The history of ideas is fascinating because often one idea leads to another which leads to a completely unexpected discovery.
Economists call this “information spillover” because freely traded ideas tend to give birth to new ideas that give birth
to still more ideas that spill from mind to mind as the process cascades into ever widening circles of knowledge and
understanding. Aristotle discovered logical principles so exact they could be expressed in symbols like those used in
mathematics. Because they could be expressed so precisely, he was able to develop a system of logic similar to geometry.
Recall that geometry begins with statements, called “axioms,” asserted as self-evident. With the addition of precise
definitions, the geometer uses precise reasoning to derive further statements, called “theorems.” Aristotle’s system
began in a similar way, with precise definitions and exact formulas asserted as self-evident. With the base established,
he derived a multitude of theorems that branched out in many directions. When he was finished, his system of logical
principles was as exact, and proven, as any system of mathematics of the day.

Some observers thought the rules of his system were too mechanical and abstract to be of any practical use. They were mistaken.
Aristotle’s system of logic was actually the first step on the path to the digital computer. The first person to design
a computing machine was a logician who, after reflecting on the exact and mechanical nature of Aristotle’s system of
logical principles, raised one of the most seminal questions ever: Is it possible to design a machine whose gears, by
obeying the “laws” of Aristotle’s logic, compute for us the exact, logically correct answer every time?

The logician who first asked the question that connected logic and computing was Raymond Lull (1232–1315), a philosopher,
Aristotelian logician, and Catholic priest. Lull has been called the “father of the computer” because he was the first
to conceive and design a logical computing machine. Lull’s device consisted of rotating cogwheels inscribed with logical
symbols from Aristotle’s system, aligned to move in accord with the rules of logic. In theory, the operator would enter
the premises of an argument by setting the dials, and the machine’s gears would then accurately crank out the logically
correct conclusion.

Lull’s design may have been primitive, but for the first time in history someone had the idea of a machine that takes inputs,
processes them mechanically on the basis of exact rules of logic, and outputs a logically correct answer. We usually
associate computing with mathematics, but the first design for a computer was based not on math but on logic—the logic
of Aristotle.

Ideas have consequences, and sometimes ideas that seem impractical have consequences that are quite practical. Lull was the
first in a long succession of logical tinkerers, each seeking to design a more powerful computing machine. You have a
cell phone in your hand right now thanks to the efforts of these innovators, each trained in logical theory. In addition
to Lull, the list includes computer pioneers Leonardo da Vinci (1452–1519), Wilhelm Schickard (1592–1635), William Oughtred
(1574–1660), Blaise Pascal (1623–1662), Gottfried Leibniz (1646–1716), Charles Babbage (1791–1871), Vannevar Bush (1890–1974),
Howard Aiken (1900–1973), and Alan Turing (1912–1954).

Thus, a continuous line of thought can be traced from Aristotle’s logical treatises to the amazing advances in logic and
computing theory of the nineteenth and twentieth centuries which led to the completion of the world’s first digital computer
(at Iowa State College in 1937) and from there to the much smaller yet more powerful devices of today. It is no coincidence
that the circuits inside every digital computer are called “logic gates.” In the logic classroom, this is my answer to
those who suppose that abstract logical theory has no practical applications.

Computer science is only one spin-off of logical theory. The subject Aristotle founded remains as vital today as it was in
ancient Athens. Aristotle probably had no idea how important his new subject would be—or how long the spillover and information
overflow would continue.

What does all of this have to do with anything? In everyday life as well as in every academic subject, reason is our common
currency. It follows that the ability to reason well is an essential life skill. But skills require knowledge as well
as practice. Since logic is the study of the principles of correct reasoning, a familiarity with elementary logic and
its applications can help anyone improve his or her life. Some people suppose logic is a useless subject; the truth may
be the reverse—it may be the most useful subject of all.

[i] An editor applied the name
Organon (“tool”) to Aristotle’s logical works after his death. The name reflects Aristotle’s claim that logic is
an all-purpose tool of thought, a guide to the precise thinking needed to attain solidly proven truth on
any subject.

For a deeper look at the fundamentals of this subject, check out the free course “Logic and Computational Thinking” published by Microsoft*. The course features material from Paul’s book Think with Socrates as well as instructional videos by Dr. Herrick.

About the author

Paul Herrick received his Ph.D in philosophy from the University of Washington. Since 1983 he has taught philosophy at Shoreline Community College, in Shoreline, Washington, near Seattle. He is the author of Reason and Worldview. An Introduction to Western Philosophy , Think with Socrates: An Introduction to Critical Thinking, The Many Worlds of Logic, and Introduction to Logic .

Other articles by Paul Herrick

Who is Socrates ? In this article in the “What is” series written for Philosophy News, Paul Herrick describes Socrates both as a thinker and as a model. One of the three major early Greek thinkers, Socrates not only lived what he believed, he died for the principle that by thinking critically we can create a life worth living.

Books by Paul Herrick

This is a comprehensive introduction to the fundamentals of logic (both formal logic and critical reasoning), with exceptionally clear yet conversational explanations and a multitude of engaging examples and exercises. Herrick's examples are on-point and fun, often bringing in real-life situations and popular culture. And more so than other logic textbooks, Introduction to Logic brings in the history of philosophy and logic through interesting boxes/sidebars and discussions, showing logic's relation to philosophy.

Brief yet comprehensive, Think with Socrates: An Introduction to Critical Thinking uses the methods, ideas, and life of Socrates as a model for critical thinking. It offers a more philosophical, historical, and accessible introduction than longer textbooks while still addressing all of the key topics in logic and argumentation. Applying critical thinking to the Internet, mass media, advertising, personal experience, expert authority, the evaluation of sources, writing argumentative essays, and forming a worldview, Think with Socrates resonates with today's students and teaches them how to apply critical thinking in the real world. At the same time, it covers the ancient intellectual roots and history of the field, placing critical thinking in its larger context to help students appreciate its perennial value.

A comprehensive look at major movements in philosophy and how those movements helped shape the way we think and behave.

*Disclosure: the course Logic and Computational Thinking was developed and largely taught by Paul Pardi, the publisher of Philosophy News who also works for Microsoft. While the course is free, it’s possible to purchase a verified certificate for the course and neither Paul receives any income from the sale of a verified certificate.

Socrates (470–399 BC) was one of the most influential philosophers in all of human history. His unique form of conversation,
the “Socratic method,” remains essential to serious philosophical inquiry twenty- four centuries after he first introduced
it.

Early Years

He was born in a modest neighborhood located just outside the south entrance to Athens. In his teens, Socrates became interested
in geometry, philosophy, and physics (subjects originally named by the Greeks). According to his student Xenophon (c.
428–c. 354 BC), Socrates and his friends met regularly to read “together the treasuries of ancient wisdom in books, and
to [make] extracts from them.”
[i] Thus, as a youth Socrates began a lifelong quest to answer the fundamental questions of life philosophically,
through reason and observation. As he discussed the great works of philosophy with his friends, he came to believe that
we learn best
not when we lock ourselves away alone like a hermit on a mountaintop, but when we actively reason with others, receiving
and giving thoughtful feedback.

Socrates served as an infantryman in the Athenian army from his teens into his fifties and fought on the front lines
in numerous military campaigns. His bravery in battle became legendary. According to all accounts, he was an utterly
fearless combat soldier. This is remarkable when you consider the nature of ancient warfare. In Socrates’s day, Greek
infantrymen, or hoplites (from
hoplon, the Greek word for “shield”), marched across the battlefield side-by-side in the phalanx formation, thousands
at a time. As the Athenian phalanx approached the opposing force, the men increased the pace to crash into the enemy
line at the “double-quick.” Blood and severed limbs would be flying everywhere. The Greek hoplite confronted the
enemy in personal, face-to-face, hand-to-hand combat. Infantry warfare in Socrates’s day was unimaginably brutal,
bloody, and horrific.
[ii] On numerous occasions his commanders tried to decorate him for extraordinary bravery, but he turned them
down, suggesting the medals be given to others.

Worldview and Lifestyle

According to his friends, Socrates cared little for fame, material possessions, or the physical comforts of life.
Reasoning with others about the big questions of philosophy mattered much more to him. While walking through
the busy
agora (marketplace) in downtown Athens one day, he is reported to have said, “So many things I can do without.”
His student Xenophon, who grew up to become a war hero, writer, and famous general, described Socrates as “frugal”
and said that even shoes were too much of a bother for him: Socrates was known to go barefoot all year long,
even on winter military campaigns and even during battles fought in the ice and snow. Every day he wore the same
old cloak too—the one he also slept in. Although he could have had more possessions, Socrates sought an uncluttered
life and practiced what is today called “voluntary simplicity.”
[iii] Socrates married late in life; he and his wife Xanthippe had three children (all boys).

Because he believed that answers to fundamental questions were best pursued in philosophical conversation with
others, Socrates could often be found sitting in the agora discussing fundamental issues with anyone who
cared to join in. According to eyewitness accounts, in these discussions he treated everyone respectfully
and as an equal. His commitment to human equality was a novel moral attitude in his day.

Those discussions in the marketplace must have been thrilling intellectual spectacles, for crowds would often
gather to listen as Socrates engaged people from all walks of life in serious conversation.

At some point around the middle of his life, at least in part as a result of these conversations, Socrates
became convinced that many people
think they know what they are talking about when in reality they do not have a clue. He came
to believe that many people, including smug experts, are in the grips of illusion. Their alleged
knowledge is a mirage. Similarly, he also saw that many
believe they are doing the morally right thing when they are really only fooling themselves—their
actions cannot be rationally justified. As this realization sank in, Socrates found his life’s purpose:
he would help people discover their own ignorance as a first step to attaining more realistic beliefs
and values. But how to proceed?

The Socratic Method

Some people, when convinced that others are deluded, want to grab them by their collars and yell
at them. Others try to force people to change their minds. Many people today believe violence
is the only solution. None of this was for Socrates. He felt so much respect for each individual—even
those in the grips of illusion and moral error—that violence and intimidation were out of the
question. His would be a completely different approach:
he asked people questions. Not just any questions, though. He asked questions designed to
cause others to look in the mirror and challenge their own assumptions on the basis of rational
and realistic standards of evidence. Questions like these: Why do I believe this? What is my
evidence? Are my assumptions on this matter really true? Or am I overlooking something? Are my
actions morally right? Or am I only rationalizing bad behavior?

Looking in the mirror in a Socratic way can be painful. For reasons perhaps best left to psychologists,
it is easy to criticize others but it is hard to question and challenge
yourself. There are intellectual hurdles as well. Which standards or criteria should
we apply when we test our beliefs and values?

Socrates, by his example, stimulated a great deal of research into this question. Over the
years, many criteria have been proposed, tested, and accepted as reliable guides to truth,
with truth understood as correspondence with reality. These standards are collected in
one place and studied in the field of philosophy known as “logic”—the study of the principles
of correct reasoning. Today we call someone whose thinking is guided by rational, realistic
criteria a “critical thinker.” Our current notion of criterial, or critical, thinking
grew out of the philosophy of Socrates.

Socrates’s unique style of conversation had such an impact on those he talked with, and
on all subsequent intellectual thought, that it has been given its own name: the
“Socratic method.”

And it works. Countless numbers of people throughout history have changed their lives
for the better by employing the Socratic method. The method of Socrates is as
relevant and alive today as it was in the fifth century BC when he challenged
his fellow Athenians to question their assumptions and values and passionately
search for the truth using their own cognitive capacities.

So, moved by the pervasiveness of human ignorance, bias, egocentrism, and the
way these shortcomings diminish the human condition, Socrates spent the rest
of his life urging people to look in the mirror and examine their assumptions
in the light of rational, realistic criteria as the first step to attaining
real wisdom. Knowledge of your own ignorance and faults, he now believed,
is a prerequisite for moral and intellectual growth. Just as a builder must
clear away brush before building a house, he would say, you must clear away
ignorance before building knowledge. As this reality sank in, his conversations
in the marketplace shifted from the big questions of cosmology to questions
about the human condition and to that which he now believed to be the most
important question of all: What is the best way to live, all things considered?

Socrates’s mission—to help others discover their own ignorance as a first
step on the path to wisdom--explains why he expected honesty on the part
of his interlocutors. If the other person does not answer honestly, he
won’t be led to examine his
own beliefs and values. And if he does not look in the mirror, he
will not advance. For Socrates, honest self-examination was one of life’s
most important tasks. This is the ultimate reason why Socrates carried
on his philosophical mission in the agora in one-on-one conversations
rather than in lectures to crowds.

This emphasis on the individual also explains why Socrates compared his
role in conversation to that of a midwife. Just as the midwife helps
the mother give birth but does not herself give birth, Socrates helps
his interlocutors give birth to more realistic beliefs of their own—truths
they discover for themselves. The philosopher Ronald Gross writes
that when Socrates acts as an intellectual midwife, we can almost
hear him saying, “Push! Push! You can bring forth a better idea!”
The Socratic process of giving birth to a better idea, Gross observes,
can be “painful.” Yet at the same time, it can be “immensely gratifying.”
[iv]

Trial and Death

Socrates had many friends; however, he also had enemies. Some in
Athens believed that Socrates was undermining the social order
when he encouraged people to question. In addition, big shots
resented him for asking them inconvenient questions in front
of everyone in the public square. Consequently, in 399 BC, when
Socrates was seventy, his opponents talked a foolish man into
pressing charges against him. Here are the (very trumped up)
formal charges, both capital offenses:

Meletus son of Meletus of Pitthos has brought and sworn this
charge against Socrates son of Sophroniscus of Alopeka: Socrates
is a wrongdoer in not recognizing the gods which the city
recognizes, and in introducing other new divinities. Further,
he is a wrongdoer in corrupting the young. Penalty, death.

He could have avoided trial by going into exile, and his
friends were ready to whisk him away to another Greek
city-state. But as a matter of principle, he insisted
on facing the charges. He would rather obey the law,
even at the risk of death, than leave his beloved city.

In accordance with the law, a jury of 501 citizens was
randomly chosen from a pool of six thousand citizens
using a mechanical selection device known as a “kleroterion.”
(The jury was large for a reason: no one could afford
to bribe that many jurors!) Each juror was paid from
public funds and swore the following oath:

I will cast my vote in consonance with the laws
and decrees passed by the Assembly and by
the Council, but, if there is no law, in
consonance with my sense of what is most
just, without favor or enmity. I will vote
only on the matters raised in the charge,
and I will listen impartially to the accusers
and defenders alike.
[v]

Socrates was known everywhere he went in Athens.
His trial was a major public event and was probably
attended by large crowds. It was held downtown
in the agora, where he had questioned the rich
and powerful for decades. The formal proceedings
began in the morning, with the jurors sitting
on benches separated from the spectators by a
barrier. The prosecution was given exactly three
hours to present its case. Once the prosecution
had concluded, Socrates was allowed the same
time for his defense, which consisted of a three-hour
speech to the jury.

Socrates’s student Plato was in the audience.
Plato was so moved by the events that morning
that he preserved Socrates’s speech in dramatic
form in a dialogue, the
“Apology” (from the Greek
apologia for “reasoned defense”), one
of many that Plato would eventually write,
each preserving and carrying forward an aspect
of his teacher’s legacy. According to Plato,
at one point in his defense, Socrates says
this to the jury:

Suppose gentlemen, you said to me, “Socrates,
you shall be acquitted on this occasion,
but only on one condition. That you
give up spending your time on this
quest and stop philosophizing. If
we catch you going on in the same
way, you shall be put to death.”
Well, supposing, as I said, that
you should offer to acquit me on
these terms, I should reply:

Men of Athens, I am your very grateful
and devoted servant, but I owe a
greater obedience to God than to
you, and so long as I have life and
strength I shall never cease from
the practice and teaching of philosophy,
exhorting you and elucidating the
truth for everyone that I meet. I
shall go on saying, in my usual way,
“My friend, you are an Athenian and
belong to a city which is the greatest
and most famous in the world for
its wisdom and strength. Are you
not ashamed that you give your attention
to acquiring as much money as possible,
and similarly with honor and reputation,
and care so little about wisdom and
truth and the greatest improvement
of the soul, which you never regard
or heed at all?”
[vi]

Socrates’s speech to the jury also included
one of his most memorable declarations:
“The unexamined life is not a life worth
living for a human being.”
[vii] Someone living the
examined life regularly looks in
the mirror and with rational standards
in mind asks the questions we have been
discussing: Are my assumptions really
true? Or am I fooling myself? What is
my evidence? Do the values I live by
reflect morality? Or am I not being honest
with myself? Am I only rationalizing
bad behavior?

In the end, although the charges were
phony, Socrates was found guilty.
[viii] The prosecution recommended
death. At this point, Socrates could
have saved his own life. According
to law, the prosecution would propose
a penalty, the defense would make
a counterproposal, and the Senate
would then choose between the two.
If Socrates had suggested a reasonable
alternative penalty, such as a stiff
fine, the Senate would probably have
accepted it. His friends were prepared
to raise any amount of money. Instead,
Socrates suggested a penalty he knew
the court would not accept: that
the city provide him with free meals
for life.
[ix] The death sentence followed.

However, because the final verdict
was handed down at the start
of a month-long civic holiday,
the law required that the execution
be postponed until the end of
the festivities. Socrates thus
spent the last month of his life
in a jail cell, surrounded by
family and friends, doing what
he loved most: discussing philosophical
issues, including the questions
of life after death and the immortality
of the soul, just like in the
old days. Several friends urged
him to escape. The jailor was
willing to help. Socrates refused,
justifying his decision with
a philosophical argument about
the nature of political obligation
and his duty to obey the law—a
Socratic argument that is still
discussed today.
[x]

In the dialogue
Phaedo, Plato tells us
that when the time came to
drink the poison, the jailor
said to Socrates:

To you, Socrates, whom
I know to be the
noblest and gentlest
and best of all who
ever came to this
place, I will not
impute the angry
feelings of other
men, who rage and
swear at me when,
in obedience to the
authorities, I bid
them drink the poison—indeed,
I am sure that you
will not be angry
with me; for others,
as you are aware,
and not I, are the
guilty cause. And
so fare you well,
and try to bear lightly
what must needs be;
you know my errand.

Plato continues:

Then bursting
into
tears
he turned
away
and went
out.
Socrates
looked
at him
and said:
I return
your
good
wishes,
and will
do as
you bid.
Then,
turning
to us,
he said,
How charming
the man
is: since
I have
been
in prison
he has
always
been
coming
to see
me, and
at times
he would
talk
to me,
and was
as good
as could
be to
me, and
now see
how generously
he sorrows
for me.
But we
must
do as
he says,
Crito;
let the
cup be
brought
. . .

In the end, even
though he
knew that
the death
he was about
to experience
would be
extremely
painful and
slow, Socrates
calmly drank
the hemlock.
You are almost
there in
person when
you read
the death
scene as
Plato records
it. Socrates
has just
taken the
poison and
is waiting
for its effects
when some
of his friends
begin to
weep. Socrates
stops them:

“What
is
this
strange
outcry?”
he
said.
“I
sent
away
the
women
mainly
in
order
that
they
might
not
offend
in
this
way,
for
I
have
heard
that
a
man
should
die
in
peace.
Be
quiet,
then,
and
have
patience.”
When
we
heard
that,
we
were
ashamed,
and
refrained
our
tears;
and
he
walked
about
until,
as
he
said,
his
legs
began
to
fail,
and
then
he
lay
on
his
back,
according
to
the
directions,
and
the
[jailor]
who
gave
him
the
poison
now
and
then
looked
at
his
feet
and
legs;
and
after
a
while
he
pressed
his
foot
hard
and
asked
him
if
he
could
feel;
and
he
said,
no;
and
then
his
leg,
and
so
upwards
and
upwards,
and
showed
us
that
he
was
cold
and
stiff.
And
Socrates
felt
them
himself,
and
said:
“When
the
poison
reaches
the
heart,
that
will
be
the
end.”
He
was
beginning
to
grow
cold
about
the
groin,
when
he
uncovered
his
face,
for
he
had
covered
himself
up,
and
said
(they
were
his
last
words)—he
said:
“Crito,
I
owe
a
rooster
to
Asclepius;
will
you
remember
to
pay
the
debt?”
“The
debt
shall
be
paid,”
said
Crito;
“is
there
anything
else?”
There
was
no
answer
to
this
question;
but
in
a
minute
or
two
a
movement
was
heard,
and
the
attendants
uncovered
him;
his
eyes
were
set,
and
Crito
closed
his
eyes
and
mouth.
Such
was
the
death
.
.
.
of
our
friend,
of
whom
I
may
truly
say,
that,
of
all
the
men
whom
I
have
ever
known,
he
was
the
wisest,
and
justest,
and
best.
[xi]

Legacy

Before Socrates,
Greek
philosophers
focused
on the
great
cosmological
questions,
such
as these:
Is there
a one
over
the many?
What
is the
ultimate
nature
of reality?
What
are the
building
blocks
of the
cosmos?
By the
sheer
force
of his
personality,
Socrates
shifted
the focus
from
broad
cosmological
speculation
to the
human
condition
and to
the following
issue:
What
is the
best
life
a human
being
can live,
all things
considered?
The Roman
philosopher
and statesman
Cicero
(106–43
BC) put
it this
way:
“Socrates
was the
first
to call
philosophy
down
from
the sky,
set it
in the
cities
and even
in the
home,
and have
it consider
life
and morals.”
[xii]

The philosopher
and noted
expert
on Socrates,
Gregory
Vlastos,
calls
the Socratic
method
“one
of the
great
achievements
of humanity”
for

. . .
it
makes
moral
inquiry
a
common
human
enterprise,
open
to
every
man.
Its
practice
calls
for
no
adherence
to
a
philosophical
system,
or
mastery
of
a
specialized
technique,
or
acquisition
of
a
technical
vocabulary.
It
calls
for
common
sense
and
common
speech.
And
this
is
as
it
should
be,
for
how
man
should
live
is
every
man’s
business,
and
the
role
of
the
specialist
and
the
expert
should
be
only
to
offer
guidance
and
criticism,
to
inform
and
clarify
the
judgment
of
the
layman,
leaving
the
final
judgment
up
to
him.
[xiii]

This
Socratic
idea,
that
each
of
us
is
capable
of
critical
thinking
and
has
the
potential
to
live
an
examined
life,
was
revolutionary
when
first
proposed.
It
marked
a
major
turning
point
in
the
history
of
thought.
Indeed,
Vlastos
calls
the
Socratic
method
the
first
major
step
toward
the
ideal
of
the
universal
moral
equality
of
all
of
humanity.
[xiv]

[xiv]
An ideal that humanity is still struggling to achieve, some twenty-four hundred years after Socrates. The same ideal was
advanced
at
about
the
same
time
by
the
Chinese
philosopher
Mozi
(c.
470–c.391
BC),
who
rejected
the
Confucian
aristocratic,
family-centered
morality
of
his
day
in
favor
of
a
morality
of
universal
concern
and
impartiality
toward
all.
Unfortunately,
the
entire
Mohist
school
was
destroyed
by
the
Qin
Emperor
in
213
BC
in
a
bloody
cultural
purge
known
as
“The
Burning
of
Books
and
the
Burying
of
Scholars.”

About the author

Paul Herrick received his Ph.D in philosophy from the University of Washington. Since 1983 he has taught philosophy at Shoreline Community College, in Shoreline, Washington, near Seattle. He is the author of Reason and Worldview. An Introduction to Western Philosophy, Think with Socrates: An Introduction to Critical Thinking, The Many Worlds of Logic, and Introduction to Logic.

Other articles by Paul Herrick

What is Logic? In this article in the “What is” series written for Philosophy News, Paul Herrick author of three logic texts gives an overview of logic, its history, and its importance. Even if you don't have a background in philosophy, you will find this summary helpful and informative.

Books by Paul Herrick

This is a comprehensive introduction to the fundamentals of logic (both formal logic and critical reasoning), with exceptionally clear yet conversational explanations and a multitude of engaging examples and exercises. Herrick's examples are on-point and fun, often bringing in real-life situations and popular culture. And more so than other logic textbooks, Introduction to Logic brings in the history of philosophy and logic through interesting boxes/sidebars and discussions, showing logic's relation to philosophy.

Brief yet comprehensive, Think with Socrates: An Introduction to Critical Thinking uses the methods, ideas, and life of Socrates as a model for critical thinking. It offers a more philosophical, historical, and accessible introduction than longer textbooks while still addressing all of the key topics in logic and argumentation. Applying critical thinking to the Internet, mass media, advertising, personal experience, expert authority, the evaluation of sources, writing argumentative essays, and forming a worldview, Think with Socrates resonates with today's students and teaches them how to apply critical thinking in the real world. At the same time, it covers the ancient intellectual roots and history of the field, placing critical thinking in its larger context to help students appreciate its perennial value.